Figure 1

Timeline, phenotype and survival of differentiating mDPSC. A) Timeline of neuronal induction protocol with successive medium changes through plating, epigenetic reprogramming, neuronal differentiation and neuronal maturation phases. Cell counts were performed at days 0, 1, 3, 5, 7, 9 and 11 to determine cell viability. B-D) Undifferentiated mDPSC had a fibroblast-like morphology in vitro. Some displayed longer processes (B,C, arrows) while a smaller population had a webbed soma (C,D arrowheads). E-F) Representative electron micrographs of undifferentiated mDPSC showing a complex ultrastructure with irregularly-shaped nuclei, widespread endoplasmic reticula (arrows) and microvilli-like projections. G-I) Representative bright field images of mDPSC at days 1 (G), 5 (H) and 11 (I) of neuronal differentiation. Cells began to develop short, thin processes by day 5 with bipolar (arrowheads) and multiprocessor (short arrows) morphologies becoming evident. By day 11 mDPSC-derived neural cells had three distinct morphologies: bipolar (long arrow), multiprocessor neural-like cells (arrows) and large, flat multiprocessor glial-like cells (arrowheads). J) Average number of live cells throughout differentiation (n = 3 differentiation batches). Cells showed a high rate of proliferation until day 3 and steadily reduced until significantly fewer cells were alive at day 11. An average of 23,000 from the original 20,000 plated per well were alive at day 11. Scale bars = 50 μm. **P <0.01.